MAN— MUSICAL POWEES. 561 



man appears to have inherited this difference from his early pro- 

 genitors. His vocal cords are about one-third longer than in wo- 

 man, or than in boys; and emasculation produces the same effect 

 on him as on the lower animals, for it "arrests that prominent 

 "growth of the thyroid, &c., which accompanies the elongation or 

 "the cords."" With respect to the cause of this difference between 

 the sexes, I have nothing to add to the remarks in the last chapter 

 on the probable effects of the long-continued use of the vocal or- 

 gans by the male under the excitement of love, rage and jealousy. 

 According to Sir Duncan Gibb,™ the voice and the form of the 

 larynx differ in the different races of mankind; but with the Tar- 

 tars, Chinese, &c., the voice of the male is said not to differ so 

 much from that of the female, as in most other races. 



The capacity and love for singing or music, though not a sexual 

 character in man, must not here be passed over. Although the 

 sounds emitted by animals of all kinds serve many purposes, a 

 strong case can be made out, that the vocal organs were primarily 

 used and perfected in relation to the propagation of the species. 

 Insects and some few spiders are the lowest animals which volun- 

 tarily produce any sound; and this is generally effected by the 

 aid of beautifully constructed stridulating organs, which are often 

 confined to the males. The sounds thus produced consist, I believe 

 in all cases, of the same note, repeated rhythmically;^ and this is 

 sometimes pleasing even to the ears of man. The chief and, in 

 some cases, exclusive purpose appears to be either to call or 

 charm the opposite sex. 



The sounds produced by fishes are said in some cases to be made 

 only by the males during the breeding-season. All the air-breath- 

 ing Vertebrata necessarily possess an apparatus for inhaling and 

 expelling air, with a pipe capable of being closed at one end. 

 Hence when the primeval members of this class were strongly ex- 

 cited and their muscles violently contracted, purposeless sounds 

 would almost certainly have been produced; and these, if they 

 proved in any way serviceable, might readily have been modified 

 or intensified by the preservation of properly adapted variations. 

 The lowest Vertebrates which breathe air are Amphibians; and ol 

 these, frogs and toads possess vocal organs, which are incessantly 

 used during the breeding-season, and which are often more highly 

 developed in the male than in the female. The male alone of the 

 tortoise utters a noise, and this only during the season of love. 

 Male alligators roar or bellow during the same season. Every one 

 knows how much birds use their vocal organs as a means of court- 



2' Owen, 'Anatomy of Vertebrates,' vol. iii. p. 603. 

 28 'Journal of the Anthropolog. Soc' April, 1869, p. Ivii. and Ixvi. 

 » Dr. Scudder, 'Notes on Stridulation,' in 'Proc. Boston Soc. of Nat 

 Hist.' vol. xl. April, 1868. 



